Period after birth: What to expect & when to speak to a doctor

In this article, we’ll walk you through what to expect when it comes to irregular periods after birth, including when to check in with your doctor. We’ll also look at what can influence your cycle — from breastfeeding to sleep and stress — and what to expect as your body finds its rhythm again.

What causes irregular periods after birth?

Your body is still recovering from pregnancy and delivery — hormone levels are shifting, your uterus is healing and shrinking back to its pre-pregnancy size, and your overall cycle is finding its rhythm again. It’s no wonder things take a little while to re-adjust!

Breastfeeding plays a huge role in getting your period after birth. Nursing raises prolactin, the hormone that supports milk production, which can temporarily pause ovulation by suppressing the hormones that trigger it. At the same time, breastfeeding lowers estrogen, the hormone that helps regulate ovulation and build the uterine lining for a period. With both prolactin high and estrogen lower than usual, your period may be delayed or unpredictable for a time [1, 2, 3].

When will I get my period after birth?

Everyone’s fertility journey is different, and when your period returns will depend on a number of factors. However, breastfeeding in particular plays a major role in how soon your period comes back. Note that the bleeding you have directly after giving birth isn’t the same as a period. It’s known as “lochia,” and your doctor will provide specific guidelines around this. Now, let’s take a closer look at the different factors that can affect when your period returns after giving birth [4]. 

If you’re breastfeeding: several months or longer
If you’re exclusively breastfeeding, your period may not return for several months or more. Prolactin — the hormone that supports milk production — can temporarily pause ovulation, which delays the return of your cycle. Some who breastfeed see their period come back starting around six months postpartum, while others don’t get a period until they stop breastfeeding altogether [2, 5].

If you're bottle feeding: soon or shortly after birth
If you’re bottle feeding your baby (i.e. not breastfeeding), your period may return sooner. Some people notice their first period just a few (5–6) weeks after giving birth, while most of those who are not breastfeeding can expect it before the two-month mark [5, 6].

There is no right or wrong way to feed your baby, and you will find the method that works best for you. Some individuals choose to exclusively bottle-feed or breastfeed, while others use a combination of both.

Other factors that can affect your postpartum menstrual cycle

While breastfeeding plays a major role in when your cycle returns, it’s not the only factor. There are also broader influences that can affect your menstrual cycle — these are things that aren’t necessarily unique to the postpartum period, but can still impact the regularity of your cycle. Understanding these factors can help you make sense of the changes in your cycle as your body heals. These are a few factors that can affect your period after birth:

• Sleep: Caring for a newborn often means disrupted sleep — shorter nights, frequent wake-ups, and difficulty staying asleep. Sleep disturbances have been linked to menstrual changes, including irregular cycles. Prioritizing rest when possible can help support your body’s natural recovery [7]. 
• Stress: Stress can disrupt your hormones and, in turn, affect your menstrual cycle. During the postpartum period, it’s common to experience emotional, physical, and mental stress, which can show up in changes to your cycle [8]. 
• Medical conditions: Hormonal conditions like PCOS or thyroid imbalances can influence how your cycle behaves after giving birth (and in general) [9]. 
• Lifestyle factors: High levels of intense exercise and rapid changes in weight can all affect your menstrual cycle, and that includes after birth [10]. 
• Smoking: The use of tobacco products has also been shown to have an effect on the regularity of the menstrual cycle [11, 12]. 
• Hormonal birth control: Birth control methods — like the progestogen-only pill, the contraceptive injection, and the intrauterine system (IUS) — can also influence your postpartum bleeding pattern. If you start hormonal birth control soon after giving birth, it may change the timing, flow, or regularity of your periods [10]. 

[13]

What are irregular periods after birth?

Irregular periods are common after birth, though they’re not exclusive to the postpartum phase — many people experience irregular cycles for a variety of reasons. After birth, “irregular” can refer to cycles that are significantly shorter or longer than the typical length (more on that below) and don’t follow a predictable pattern. It can also refer to changes in bleeding patterns, including abnormal or unexpected bleeding.

Irregular periods after birth can mean:

• The number of days between one period and the next keeps changing (in other words, your cycle length varies by more than 7–9 days) 
• Menstrual cycles that are shorter than 21 days or longer than 35 days
• Periods that last longer than seven days
• Flow that’s heavier or lighter than usual
• Severe pain during your period
• Spotting between periods or bleeding during or after sex

[14, 15]

It’s important to note that irregular periods are different from postpartum bleeding (lochia), which occurs in the weeks immediately after birth (more on this below). 

Postpartum recovery is already a lot to manage, and when your cycle doesn’t follow a pattern, it can be even more challenging. At Natural Cycles, we know that knowledge is power, and that’s why we built NC° Postpartum. With this app experience, you can confirm and predict ovulation, log bleeding, monitor flow changes, and get guidance on what’s typical versus when it may be time to check in with your doctor. Plus, when your period comes back, you can use NC° Birth Control, the FDA-cleared, hormone-free way to prevent pregnancy.

When to contact your doctor about irregular periods after birth

Some variation in your cycle is normal — hormones naturally ebb and flow after pregnancy. However, irregular periods can sometimes need attention. Reach out to your doctor if:

• You started your period, but haven’t gotten another for several months (around 3–6) 
• You have heavy bleeding (soaking through a tampon/pad every hour) and/or feel dizzy during your period
• Your periods last longer than seven days 
• It's been more than 6 weeks since you gave birth, and you are still bleeding
• Your periods are significantly different (e.g., more painful) than they were pre-pregnancy

[15, 16]

After giving birth, your doctor will walk you through what to expect in terms of your returning menstrual cycle, and provide guidance on when to reach out. You’ll also be scheduled for postpartum checkups to address any concerns or ask clarifying questions about your cycle.

That said, no one knows your body better than you. If something feels unusual or doesn’t seem right, trust your instincts and reach out — it’s always better to check in early.

How long does it take for periods to regulate after birth?

This depends on several factors, including whether or not you’re breastfeeding. Your cycle may take several months — or even more than a year — to become regular again. After all, your body has undergone enormous hormonal changes to support pregnancy and birth, and it takes time for everything to return to its usual pattern, whatever that means for you [1]. 

Can I get pregnant with irregular periods after birth?

Yes, it’s possible to get pregnant after birth if you’re experiencing irregular periods. 

Pregnancy after birth can happen even if your first period hasn’t come back, and even if you’re breastfeeding. That’s because ovulation (when your body releases an egg) happens before a period in the menstrual cycle, so you may be fertile without realizing it. Even if your periods are irregular, it’s likely you are still ovulating, and thus it’s possible to get pregnant. 

If you’ve just given birth and are trying to avoid getting pregnant, it’s a good idea to start thinking about contraception — again, even before your first period comes back. There are a few options available. Your doctor may offer to fit an IUD at birth or prescribe hormonal contraception in the weeks after giving birth [17]. 

If you’re breastfeeding exclusively (every 4 hours during the day and 6 hours at night), it’s possible to use this as a form of contraception. Breastfeeding as a form of birth control is known as LAM, (lactational amenorrhea) and can be used for up to six months after giving birth [18, 19]. 

If you’re interested in non-hormonal birth control, you can also use Natural Cycles to prevent pregnancy. You’ll be notified as your ovulation returns and your cycle begins to stabilize. After the postpartum period ends, you can switch to using NC° Birth Control. Keep in mind that until the app detects your ovulation day, you’ll need to use a backup method like condoms.

Navigating your postpartum journey with Natural Cycles

From irregular cycles to mood changes, the postpartum phase can feel overwhelming, but Natural Cycles can help. With NC° Postpartum, you can track key parts of your recovery — from postpartum bleeding and sleep patterns (because rest matters!) to the return of ovulation and your period. The app also offers tailored educational resources on topics like feeding routines and postpartum hair loss, so you have guidance at every step. When you’re ready, you can transition to using the app to prevent pregnancy with FDA-cleared contraception.

Whether you’re trying to get pregnant, seeking non-hormonal birth control, or navigating postpartum, learn more about how Natural Cycles can work for you.